Prediction of Solvent Effects on Rate Constant of [2+2] Cycloaddition Reaction of Diethyl Azodicarboxylate with Ethyl Vinyl Ether Using Artificial Neural Networks

The photosolvolysis of 1- and 2-hydroxy-9-fluorenols 4-6 has been studied in aqueous solution. All of these 9-fluorenols photosolvolyze efficiently in 1:1 H2O-CH3OH, to give the corresponding methyl ether products in high chemical and quantum yields. Whereas the photosolvolysis of the parent 9-fluorenol (2, R = H) is known to proceed via the very short-lived and formally ground-state antiaromatic 9-fluorenyl cation (1, R = H), the photosolvolysis of 1-hydroxy-9-fluorenol (4) proceeds via a much longer-lived (approximately = 5-10 s) fluorenyl quinone methide 9, which is trappable by ethyl vinyl ether via a [4+2] cycloaddition reaction to give a chroman derivative. Interestingly, 2-hydroxy-9-fluorenol (5) photosolvolyzes via a very short-lived intermediate with similar lifetimes as observed for the 9-fluorenyl cation (1, R = H), although a corresponding fluorenyl quinone methide intermediate is accessible for this compound. This study demonstrates that the mechanism of photosolvolysis of these types of compounds can be dramatically altered when an aryl hydroxy group is present.Key words: photosolvolysis, 9-fluorenyl cation, quinone methide, carbocation, antiaromatic.

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Prediction of ozone tropospheric degradation rate constant of organic compounds by using artificial neural networks

Analytica Chimica Acta ◽

10.1016/j.aca.2005.09.033 ◽

2006 ◽

Vol 556 (2) ◽

pp. 355-363 ◽

Cited By ~ 45

Author(s):

M.H. Fatemi

Keyword(s):

Neural Networks ◽

Artificial Neural Networks ◽

Organic Compounds ◽

Rate Constant ◽

Degradation Rate ◽

Degradation Rate Constant ◽

Artificial Neural

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Estimation of flotation rate constant and collision efficiency using regression and artificial neural networks

Separation Science and Technology ◽

10.1080/01496395.2017.1386216 ◽

2017 ◽

Vol 53 (2) ◽

pp. 374-388 ◽

Cited By ~ 8

Author(s):

Amir Eskanlou ◽

Behzad Shahbazi ◽

Behzad Vaziri Hassas

Keyword(s):

Neural Networks ◽

Artificial Neural Networks ◽

Rate Constant ◽

Collision Efficiency ◽

Flotation Rate ◽

Artificial Neural

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Computational Study on the Mechanism of Cycloaddition Reactions of Bissulfonyl-1,3-butadiene with Some Alkenes

Letters in Organic Chemistry ◽

10.2174/1570178617666200210112307 ◽

2020 ◽

Vol 17 (10) ◽

pp. 735-742

Author(s):

Sepideh Masoumifar ◽

Mina Haghdadi ◽

Hassan Ghasemnejad Bosra

Keyword(s):

Vinyl Ether ◽

Energy Barrier ◽

Computational Study ◽

Cycloaddition Reaction ◽

Dft Method ◽

Ethyl Vinyl Ether ◽

Cycloaddition Reactions ◽

Ethyl Vinyl

The cycloaddition reactions of 2,3-bis (ethylene sulfonyl)-1,3-butadiene with 2,3-dimethyl- 1,3-butadiene, cyclopentadiene, 2-methyl prop-2-enoate and ethyl vinyl ether have been theoretically studied using the DFT method at the MPWB1K/cc-pVDZ level of theory. There are two possible modes of participation in each reaction (2π and 4π electron), of which the 2π electron is preferred. The energy results indicate that formations of the [2+4] cycloadducts are favored kinetically. The stereoselectivity of the [2+4] cycloaddition reaction of 2,3-bis (ethylene sulfonyl)-1,3-butadiene with cyclopentane is the highest and the energy barrier for this process is the lowest.

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